Double tapered guidance method



Dec. 23, 1969 B. J. WATKINS DOUBLE TA PERED GUIDANCE METHOD OriginalFiled Nov. 29, 1963 2 Sheets-Sheet 2 INVENTOR.

Bea/:5 J War-mus BY p%%% United States Patent 0 M 3,485,051 DOUBLETAPERED GUIDANCE METHOD Bruce I. Watkins, Palos Verdes Estates, Califi,assignor to Regan Forge & Engineering Co., San Pedro, Calif., acorporation of California Original application Nov. 29, 1963, Ser. No.326,738, now Patent No. 3,347,567, dated Oct. 17, 1967. Divided and thisapplication May 22, 1967, Ser. No. 640,274

Int. Cl. E02d 25/00; E21b 41/00; B23q 11/02 US. Cl. 61-46.5 8 ClaimsABSTRACT OF THE DISCLOSURE A method of guiding and prealigning couplingmembers in subsea locations remote from a floating vessel from which oneof the coupling members is lowered including establishing at least twovertically spaced annular coaxial abutment surfaces of differentdiameters on a casing head, establishing at least two vertically spacedannular coaxial abutment surfaces of different diameters on a casinghead, establishing at least two axially spaced coaxial annular guidancesurfaces of different diameters within a casing coupling member, movingthe coupling member into engagement with the casing head to bring thetwo axially spaced abutment surfaces into engagement with the twoaxially spaced guidance surfaces in axially spaced double surfaceengagement to loosely prealign the coupling member axially to the casinghead and thereafter moving the coupling member from the prealignedposition into a completely landed or tightly coupled position. Bothlarge and small diameter concentric annular abutment and guidancesurfaces, respectively, are axially spaced from each other substantiallyequal distances and the double surface engagement is establishedconcurrently to loosely prealign a multi-diameter coupling member to amulti-diameter inner bored casing head.

Cross-references to related applications This application is adivisional application of my copending application Ser. No. 326,738,filed Nov. 29, 1963, now Patent No. 3,347,567, entitled Double TaperedGuidance Method and Apparatus.

Background of the invention This invention relates in general to amethod for interconnecting a pair of conductors or conduits in a subseaenvironment remotely of a floating vessel or platform from which atleast one of the conductors or conduits is run. More particularly, theinvention in its preferred form relates to a method for guiding andaligning a subsea well landing tool or bonnet onto a subsea conductorpipe head or the like where the landing tool is suspended from aconductor run from the vessel or platform and may approach the conductorpipe head in a tilted or vertically misaligned manner.

In subsea oil well drilling, completion, re-entry and productionoperations, it is necessary repeatedly to engage, connect and seal twoconductors or conduits together at a location beneath the sea remotefrom the floating platform or vessel from which the operations areconducted. In many such operations, it is necessary to connect bothlarge and small diameter concentric tubular members simultaneously. Suchconnections are frequently required when landing a production ordrilling bonnet on a well head where the well head includes a casing ortubing hanger suspended in and extending upwardly of the well headcemented into the well. Particularly in subsea oil well drilling, theconnections of casings beneath the sea requires fluid-tight seals tomaintain Well pressures,

3,485,051 Patented Dec. 23, 1969 retain well and hydraulic fluids andkeep high pressure sea water out of the well and casings. Thepreservation and protection of sealing means between the casings oncoupling and uncoupling beneath the sea beyond the working depth ofdivers is of prime consideration. Also, it is believed that whether suchmulti'diameter coupling members are assembled on board a rolling orpitching floating vessel or beneath the sea remote from the vessel, animproved means of guiding and aligning the couplings together prior totheir complete connection is required.

It is the principal object of this invention, therefore, to disclose andprovide a method and apparatus for use with casing couplings, landingtools or drilling or production bonnets for prealigning multi-diameterconcentric casings and tubings prior to their complete connection toalign internal sealing means and cooperating sealing surfaces prior tothe sealing abutment thereto on complete connection of the couplings orthe like.

It is another object of this invention to disclose and provide a landingtool or coupling particularly adapted for use in landing marineconductor pipes or casings run from a floating vessel onto a stationarysubsea conductor pipe head including two concentrically mountedvertically spaced casing heads.

It is a further object of this invention to disclose and provide amethod and apparatus for use in connecting a movable coupling memberonto a stationary, remotely located casing member to effect an axialprealignment of said members prior to their complete coupling together.

It is still another object of this invention to disclose and provide amethod and apparatus for remotely engaging, aligning and connecting apair of easing means, each including both large and small concentricdiameter members, together in a simple, easily accomplished manner"without the need for additional, auxiliary guides or prealignment meansother than the coupling portions of the casing means themselves.

Summary of the invention Generally stated, the method of the presentinvention comprises the provision of at least two vertically spaced,concentric abutment surfaces on a first male coupling member, as on astationary subsea oil well head. A pair of axially spaced, concentricand generally annular guidance surfaces are provided within a secondfemale coupling member, as on an oil well drilling bonnet or well headlanding tool. The second coupling is then moved into engagement with thefirst coupling, as by running a drilling bonnet on the lower end of amarine conductor to a well head. On engagement of the first and secondcoupling members, prior to a complete connection where internal sealingmeans are operative, the couplings are prealigned by at least a doubleor dual surface engagement between axially spaced abutment surfaces ofthe first coupling member and the two axially spaced, concentricgenerally annular guidance surfaces within the second coupling member.In accordance with the present method, such double axially spacedabutment or aligning engagement occurs concurrently to axially prealignsaid coupling members prior to their complete assembly or connection. Onsuch prealignment, in which any sealing means between mating couplingsurfaces are also aligned, the coupling members are thereafter movedaxially relative to each other and stopped at a completely connectedposition by a pair of abutment or stop means intermediate of theaforementioned guidance surfaces.

A further understanding of the method and apparatus of the presentinvention may be obtained by a consideration of the following detaileddescription of an exemplary embodiment of the double tapered guidanceapparatus employing the method of the present invention. Reference 3will be made to the accompanying sheet of drawings in which:

FIG. 1 is a vertical section view of an exemplary well head latchmechanism and associated landing tool apparatus employing the method andapparatus of the present invention shown partly engaging but misalignedover a well head;

FIG. 2 is a vertical section view of the apparatus of FIG. 1 with thelanding tool apparatus pivoted into generally aligned relation to andover the well head prior to complete connection;

FIG. 3 is a vertical section view of the apparatus of FIGS. 1 and 2shown in axially prealigned relation prior to complete connection to thewell head; and

FIG. 4 is a vertical section view of the apparatus of FIGS. 1, 2 and 3completely connected to the well head.

Referring to the drawings, an exemplary embodiment of the double taperedguidance apparatus, in accordance with the present invention, is shownand will now be explained in detail. A marine conductor 10, having aflange 11, is shown bolted to a marine conductor adapter flange 12 bybolts 13. Adapter flange 12 is shown bolted by bolts 14 to an examplaryform of well head latch indicated generally at 15.

The exemplary well head latch indicated generally at 15 includes a lowerbody portion 16 and an upper body portion 17. A plurality of verticallypositioned preferably hydraulically operated latch mechanisms 18 aremounted on the upper body portion 17, each such mechanism being adaptedto selectively operate a camming block 19 against a dog 20 through apush rod 21 as shown in FIG. 1.

Sealing means 22 are provided within the bore 23 of upper body portion17 with a retaining ring 24 provided between the sealing means 22 andadapter flange 12. Additional sealing means 25 are provided between theseal retaining ring 24 and the adapter flange 25 as shown in FIG. 1.

An exemplary double tapered landing tool in accordance with the presentinvention is indicated generally at and, in the exemplary embodiment,comprises a cylindrical bonnet or coupling member 31.

A conductor pipe 40, may be cemented into a well, as the conductor pipe17 in my co-pending application Ser. No. 326,917, filed Nov. 29, 1963,entitled Subsea Well Control Tube Methods and Apparatus. A second,smaller diameter casing extends concentrically and upwardly of thecasing 40. In the exemplary embodiment a casing head or hanger 41 ismounted concentrically within the conductor 40 to suspend the casing ortubing 42 down within conductor 40 to the well. The casing head orhanger 41 shown is of the flow through type with a passage at 43provided between the casing and conductor walls which communicates withthe well.

It should be understood that the description of apparatus thus far isexemplary only of one of many instances wherein it is desired to land amarine conductor on a stationary subsea conductor pipe head from aremote floating vessel or platform where the conductor pipe headincludes a first conductor pipe, as conductor pipe 40, with a secondconductor pipe or casing, as casing 41, concentric to and extendingupwardly above the first conductor pipe.

In accordance with the present invention, the landing tool, indicatedgenerally at 30, is provided with a first and second conical guidancesurface to engage, align and guide the landing tool and associated wellhead latch and conductor pipe apparatus down onto the exemplaryconductor pipe including the conductors or casings 40 and 41. Thelanding tool in the exemplary embodiment includes a generallycylindrical body portion 31 which is provided with a two-stage innerbore including bore portion 32 adapted to slidably fit over the largediameter exterior surface 44 of conductor pipe 411 and a smaller boreportion 33 adapted to slidably fit over the reduced diameter or headportion 45 of the conductor pipe 40. An

annular landing means or surface 34 is provided on the interior of thegenerally cylindrical body portion between bore portions 32 and 33 andis adapted to seat upon the circular landing ledge 35 provided on theconductor pipe 40 between portions 44 and 45.

The lower bore portion 26 of the well head latch, indicated generally at15, is adapted to slide over and fit upon the larger diameter area 46 ofthe inner conductor or casing 41 and the smaller bore portion 23 of theWell head latch is adapted to' slide upon and fit about the smallerdiameterarea 47 of the upper or head portion of the casing or innerconductor 41. Also, an annular landing means or surface 27 'is providedin the interior of the well head latch indicated generally at 15 betweenthe bore portions 23 and 26 to land upon the circular landing ledge orstop 48 on the inner conductor or casing 41 between the large diameterarea 46 and the small diameter area 47. Therefore, to completely landthe conductor 10 and its associated well head latch, indicated generallyat 15, on the well head, including the conductor pipe 40 and innerconductor or casing 41 in the exemplary embodiment, the landing means orsurfaces 27 and 34 must rest upon the ledge or stop surfaces 48 and 35respectively, as shown in FIG. 3.

A first guidance surface 50 is provided on the lower end of the bodyportion 31. Surface 50 extends .downwardly and outwardly of the bodyportion 31 to provide a downwardlyfacing concave guidance surface tosuecessively receive and guide the two conductor casings or concentriccasings 40 and 41. A second tapered guidance surface 51 is provided atthe upper end of body portion 31. Surface 51 extends upwardly andinwardly of the body portion 31 providing an inner downwardly facingconcave guidance surface spaced vertically from and above the firstguidance surface 50. In the exemplary embodiment surface 51 is providedby a threaded collar 52 mounted to the body 31 but may be made integraltherewith as surface 50 is shown.

In accordance with the present invention, the first and second guidancesurfaces 50 and 51 associated with the body portion of the landing tool,or female coupling member as indicated generally at 30, are verticallyspaced from each other the same distance that the second or innerconductor pipe or casing 41 extends upwardly of the outer or firstconductor pipe 40. This relationship of surfaces 50 and 51 to casings 40and 41 is necessary to the practice of the method of the presentinvention. Prior to the complete landing of the landing tool, couplingor bonnet, as indicated generally at 30, on the well head includingcasings 40 and 41, the first guidance surface 50 may engage and guidethe cylindrical abutment surface on the upper end of the inner casing orconductor pipe 41 and direct it within the bore portion 32 of the body31. On further downward landing movement of the landing tool or femalecoupling member onto the male coupling members 40 and 41, the firstabutment surface 60 may engage and be directed by the second or upperguidance surface 51 as shown in FIG. 1. On pivoting of the couplingmember on the casing head, the second or lower cylindrical abutmentsurface 61 on the outer conductor pipe 40 may be pivoted into the loweror outer guidance surface 50 on further assembly movement thereof intoan axially prealigned position as shown in FIG. 2.

In the exemplary embodiment described, the contact between the couplingor landing tool and the casing heads prior to pivoting of the couplingto the position of FIG. 2 occurs between the abutment surface 60 andguidance surface 51. It is also possible in landing the coupling or toolon the casing heads that such contact may occur between the abutmentsurface 61 and guidance surface 50 prior to the pivoting movement of thecoupling to the aligned position of FIG. 2. In either instance, however,there is an initial contact between either the abutment 60 and surface51 or between abutment 61 and surface 50 and a subsequent pivotingmovement of the coupling to bring surfaces 50 and 51 into contact withabutments 61 and 60, respectively, concurrently, if but for only a veryshort duration. Because of the relatively loose fit between the couplingmember and casing heads in the double guidance contact position of FIG.2, the coupling may be easily moved into the loose fitting, generallyaxially aligned position to the casing heads 40 and 41, as shown in FIG.3. i

It should be noted that the fit of each of the bore portions 23, 26, 33and 32 over and about the casing head outer surface portions 47, 46, 45and 44, respectively, are snug fits on complete assembly of the couplingmember or landing tool, indicated generally at 30, on the casing headportions 40 and 41, at the axial prealignment position of FIG. 4. Thefit between bore surfaces 26, 33 and 32 and casing head outer surfaceportions 47, 46 and 45 shown in FIG. 3, are loose fits allowing an easyprealignment or preassembly of the apparatus parts at a remote subsealocation when operating from a floating and possibly rolling or pitchingvessel. The axial alignment of the apparatus in accordance with thepresent invention is thereby effected prior to the mating of any closetolerance sealing surfaces.

The provision of the two vertically spaced guidance surfaces 50 and 51thus allows the engagement and axial alignment of the two verticallyspaced cylindrical abutment surfaces 60 and 61, causing the landing tool30 and associated well head latch and conductor pipe of the exemplaryembodiment to become vertically aligned over the well head, as shown inFIG. 3, prior to the complete landing of the landing surfaces 27 and 34upon the ledges or stop surfaces 48 and 45, respectively, as shown inFIG. 4. Such prior alignment of the landing tool, bonnet or couplingover the multi-diameter well head, conductor pipe or casing heads inaccordance with the present invention greatly facilitates the landingand connection of such conductors and/ or couplings without damaging orimpairing internal sealing means, such as the seal means 22 andparticularly the seal means 49 on the interior of the exemplary landingtool body 31.

Having thus described an exemplary embodiment of the double taperedguidance method and apparatus in accordance with the present invention,what I wish to claim as new and secure by Letters Patent is defined andlimited only by the following claims.

I claim:

1. A coupling guidance method for use in landing coupling members onstationary subsea casing heads remote from a floating vessel from whichthe coupling mem ber is lowered comprising the steps of:

running a coupling member from a floating vessel on a conductor pipe toa remote stationary subsea casing head;

establishing a first contact between annular tapered guidance surface onsaid coupling member and a first abutment surface on said casing head;

pivoting said coupling member on said first contact and establishing asecond contact between a second annular tapered guidance surface on saidcoupling and a second abutment surface on said casing head; and

moving said axially aligned coupling member and casing head relative toeach other to effect coupling thereof.

2. The method of claim 1 wherein said first and second guidance surfacesare axially spaced on said coupling member generally the same distancesaid first and second abutment surfaces are axially spaced on saidcasing head and including the further step of establishing said firstand second contacts concurrently to prealign said coupling member andcasing head prior to coupling thereof.

3. A method of prealigning a casing coupling member on a stationarysubsea casing head means remote from a floating vessel from which thecoupling member is lowered including the steps of:

establishing at least two vertically spaced concentric abutment surfaceson a subsea casing head means;

providing at least two axially spaced concentric annular taperedguidance surfaces within a. casing coupling member;

running said coupling member on a casing from said vessel intoengagement with said casing head means to bring said two abutmentsurfaces into abutment with said two guidance surfaces to axiallyprealign said coupling member on said casing head means; and

thereafter moving said coupling member from said prealigned positioninto a coupled position with said coupling seated on said casing headmeans.

4. A method of guiding, prealigning and landing a multi-diameter borelanding tool from a floating vessel down upon a remotely locatedmulti-diameter subsea well casing head comprising the steps of:

forming a pair of vertically spaced and relatively axially immovableconcentric annular abutment surfaces on the exterior of a multi-diametercasing head having a large diameter lower portion and a smaller diameterupper portion;

forming a pair of vertically spaced and relatively axially immovableconcentric annular tapered guidance surfaces within a multi-diameterbore landing tool having a large inner diameter lower bore portion and asmaller inner diameter upper bore portion, said bore portions beingformed to fit over said head portions;

mounting said casing head at a stationary subsea first well casing andmounting said landing tool on a second well casing to be lowered to andcoupled to said first well casing;

lowering said landing tool by its associated second casing from afloating vessel toward said casing head and guiding said lower boreportion over said upper head portion by lowering said guidance surfaceover said upper abutment surface;

lowering said landing tool further down on said casing head andestablishing a dual vertically spaced guidance engagement by the lowerguidance surface engaging the lower abutment surface and the upperguidance surface engaging the upper abutment surface and guiding saidtool large bore portion over said head large diameter portion and saidtool smaller bore portion over said head smaller diameter portionconcurrently by said dual guidance engagement; and

thereafter landing said tool down on said casing head by still furtherlowering of said tool down on said head after said large and smallertool bore portions have been prealigned over said large and smallerdiameter head portions, respectively, said abutment surfaces passingthrough and disengaging from said guidance surfaces prior to complete:landing of said tool on said head.

5. The method of claim 4 including the steps of:

loosely fitting said landing tool on said casing head by said abutmentsurfaces passing through and disengaging from said guidance surfaces;and

snugly fitting said landing tool bore portions over said casing headdiameter portions by a further axially spaced dual guidance engagementbetween said tool and head prior to complete landing of said tool onsaid head.

6. The method of claim 4 including the steps of:

providing a landing surface in said bore between said large and smallerbore portions and. a landing ledge on the exterior of said casing headbetween said large and smaller diameter portions during said formingsteps; and

seating said landing surface upon said landing ledge during said step oflanding said tool down on said casing head.

7. A coupling guidance method for use in landing coupling members onsubsea casing heads remote from a floating vessel from which thecoupling member is lowered comprising the steps of:

running a multi-diameter inner bore coupling member from a floatingvessel on a conductor pipe to a remote stationary subsea multi-diametercasing head;

establishing a first engagement between a first annular tapered guidancesurface on said coupling member and a first abutment surface on saidcasing head;

establishing a second engagement between a second annular taperedguidance surface on said coupling axially spaced therein from said firstguidance surface and a second abutment surface on said casing headaxially spaced thereon from said first abutment surface a distance equalto the spacing of said guidance surfaces;

guiding said first coupling member into a loose fitting generallyaxially aligned position on said second coupling member by moving saidfirst and second guidance surfaces over and past said first and secondabutment surfaces;

References Cited UNITED STATES PATENTS 895,750 8/1908 Harms et al.285l33 2,552,899 5/1951 Manes 6146.5 2,962,096 11/1960 Knox 285l8 X3,023,012 2/1962 Wilde 285--18 X 3,241,864 3/1966 Shaffer 285I8 CHARLIET. MOON, Primary Examiner US. or. X.R.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,485,051 December 23, 1969 Bruce J. Watkins It is certified that errorappears in the above identified patent and that said Letters Patentarehereby corrected as shown below:

Column 5, line 55, before "annular" insert an Signed and sealed this27th day of October 1970.

(SEAL) Attest:

Edward M. Fletcher, Jr.

Attesting Officer Commissioner of Patents WILLIAM E. SCHUYLER, JR.

